TOPCon Solar Cells With Al-Free Ag and Cu Metallization: Strategies for Ag Reduction in Industrial Silicon Solar Cells

Jan Lossen; Pirmin Preis; Mertcan Comak; Joris Libal; Dominik Rudolph; Jan Hoß; Lejo Joseph Koduvelikulathu

doi:10.52825/siliconpv.v2i.1316

Authors

Jan Lossen International Solar Energy Research Center Konstanz https://orcid.org/0000-0003-4981-8674
Pirmin Preis International Solar Energy Research Center Konstanz
Mertcan Comak International Solar Energy Research Center Konstanz
Joris Libal International Solar Energy Research Center Konstanz
Dominik Rudolph International Solar Energy Research Center Konstanz https://orcid.org/0000-0003-0742-284X
Jan Hoß International Solar Energy Research Center Konstanz
Lejo Joseph Koduvelikulathu International Solar Energy Research Center Konstanz

DOI:

https://doi.org/10.52825/siliconpv.v2i.1316

Keywords:

Ag-Reduction, Cu-Paste, Sustainability, TOPCon, Metallization

Abstract

This work presents an approach to lower the silver consumption of screen printed TOPCon (Tunnel Oxide Passivated Contact) solar cells by reducing and partially replacing the silver by low cost copper metallization paste. On the solar cells front side an adapted process sequence enables the use of a pure Ag paste, which compared to the industrially established AgAl paste offers a better conductivity and respectively requires less laydown to enable similarly low grid resistance. On the solar cells rear side the conductivity of the metal grid is accomplished by a copper paste which is realized within a print-on-print step on top of the Ag contact layer with minimized laydown. A reduction in Ag paste consumption by 40% to less than 9 mg/ W_p without sacrificing conversion efficiency seems achievable and can enable a significant cost reduction for TOPCon solar cells.

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References

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TOPCon Solar Cells With Al-Free Ag and Cu Metallization

Strategies for Ag Reduction in Industrial Silicon Solar Cells

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